(1) Field of the Invention
The present invention relates to a store-and-forward type of electronic conference system, and particularly to a technique for automatically judging or correcting, when occurred, an inconsistency in the contents of informations to be exchanged.
(2) Related art of the Invention
Generally, an "electronic conference system" designates or specifies those systems constituted for information-exchange between unspecified number of users. In a large-scale electronic conference system, the users of the electronic conference system are registered at each of geographically separated areas (hereinafter called "site"). The registered user can use only the site at which he has been registered.
In such an electronic conference system, there is generally adopted a store-and-forward type of communication system, such as in view of transmission speed of communication lines connecting between the sites. That is, the information generated at each of the sites is once stored into a transmission queue which stores informations to be transmitted, and then collectively or batch transmitted at each of a predetermined time of period. The information received at each sites other than the transmitting sites is once stored into a reception queue for storing received informations, and then processed by that background which has processing ability to spare.
Typically, electronic conference systems utilize those unit containers named "forum" established in a hierarchy structure. In turn, each of the forums includes hierarchical messages as informations, also in a hierarchy structure.
However, in such an electronic conference system, there is adopted the store-and-forward type of communication system, so that there may occur inconsistency in the informations to be transmitted. For example, it is now assumed that the informations are exchanged between a forum A of a site A and a forum A of a site B, and forums B, B are established at the lower levels of sites A, A, respectively. Under this state, there may be lost the forum A and its lower level of forum B both at the site B, due to a certain cause (for example, cut-off of power such as due to power failure). Then may occur such a situation that the forums in site B are recovered based on the contents of a recovery disk, to cause the state in which the forum B had not been established at the lower level of the forum A in site B, due to the oldness of the recovery disk. Under such a state, if it is tried by the site A to write (i.e., create) a message into the vanished forum B of site B, an informational operation is performed at site B for the not existing forum B. Thus, inconsistency in information contents should occur.
In the conventional technique, it has been difficult to find out such an information inconsistency even when it happened, resulting in such a situation that the administrator of the electronic conference system could not get aware of it for a long time. This situation is not so problematical, insofar as the exchangee-information to be exchanged between each of the sites is not so important. However, the situation is problematic if the information is extremely important or a prompt treatment is required, since an inconsistency, if any, in the transmittee information may result in that the transmitted information is not correctly reflected at the site which receives this information.